Index: lib/Support/Host.cpp
===================================================================
--- lib/Support/Host.cpp
+++ lib/Support/Host.cpp
@@ -686,7 +686,7 @@
 }
 #endif
 
-#if defined(__linux__) && defined(__arm__)
+#if defined(__linux__) && (defined(__arm__) || defined(__aarch64__))
 bool sys::getHostCPUFeatures(StringMap<bool> &Features) {
   std::string Err;
   DataStreamer *DS = getDataFileStreamer("/proc/cpuinfo", &Err);
@@ -715,8 +715,22 @@
       break;
     }
 
+#if defined(__aarch64__)
+  // Keep track of which crypto features we have seen
+  // 0001 = aes
+  // 0010 = pmull
+  // 0100 = sha1
+  // 1000 = sha2
+  uint32_t crypto = 0;
+#endif
+
   for (unsigned I = 0, E = CPUFeatures.size(); I != E; ++I) {
     StringRef LLVMFeatureStr = StringSwitch<StringRef>(CPUFeatures[I])
+#if defined(__aarch64__)
+      .Case("asimd", "neon")
+      .Case("fp", "fp-armv8")
+      .Case("crc32", "crc")
+#else
       .Case("half", "fp16")
       .Case("neon", "neon")
       .Case("vfpv3", "vfp3")
@@ -724,12 +738,32 @@
       .Case("vfpv4", "vfp4")
       .Case("idiva", "hwdiv-arm")
       .Case("idivt", "hwdiv")
+#endif
       .Default("");
 
+#if defined(__aarch64__)
+    // We need to check crypto seperately since we need all of the crypto
+    // extensions to enable the subtarget feature
+    if (CPUFeatures[I] == "aes")
+      crypto |= 0x1;
+    else if (CPUFeatures[I] == "pmull")
+      crypto |= 0x2;
+    else if (CPUFeatures[I] == "sha1")
+      crypto |= 0x4;
+    else if (CPUFeatures[I] == "sha2")
+      crypto |= 0x8;
+#endif
+
     if (LLVMFeatureStr != "")
       Features.GetOrCreateValue(LLVMFeatureStr).setValue(true);
   }
 
+#if defined(__aarch64__)
+  // If we have all crypto bits we can add the feature
+  if (crypto == 0xf)
+    Features.GetOrCreateValue("crypto").setValue(true);
+#endif
+
   return true;
 }
 #else